Abstract: The present invention is a self-destructive syringe that includes a cylindrical body with a hypodermic needle at one end, a breakable circle, and a retaining ring. The syringe has a piston with a sharp point at the front of the piston. When the piston reaches the lower end of the stroke, the sharp point on the piston perforates the breakable circle while the edges of the piston are encased in the retaining ring. The retaining ring has cutting edges which will damage the seal of the piston if the piston is returned for reuse. A seal, supported by flanges, is positioned at an opposite end of the syringe so as to prevent the piston from reaching the destructive end of the syringe.